Robust Variable-Step Perturb-and-Observe Sliding Mode Controller for Grid-Connected Wind-Energy-Conversion Systems. - Ilham Toumi; Billel Meghni; Oussama Hachana; Ahmad Taher Azar; Amira Boulmaiz; Amjad J. Humaidi; Ibraheem Kasim Ibraheem; Nashwa Ahmad Kamal; Quanmin Zhu; Giuseppe Fusco; Naglaa Kamel Bahgaat (Entropy, 2022)